Methods to Determining Cleanliness in Parts Washing

Methods to Determining Cleanliness in Parts Washing

pharmaceutical beakers and test tubes

Table of Contents

What methods are used for determining cleanliness in the part-washing process?

Water-Break Test:

  • Take a cleaned and dried part and set it in a vertical position
  • Use a spray bottle containing distilled water
  • Spray the part two to three times from at least 6″ away
  • The water spray should sheet off if the part is clean and free of oily residue
  • The water will tend to bead on the part if some oily residue remains

UV Black Light:

  • Take the cleaned and dried part and the black light into a dark area
  • In the dark area, shine the black light onto the part 
  • It should not highlight any fluorescence if the part is free of soils
  • You should see some fluorescence where the soil is present; if some soil remains
  • You should check a dirty part for florescence to ensure that the soil emits fluorescence when viewed under a black light

Clean-wipe test:

  • Take the cleaned and dried part and wipe it with a portion of a clean, white, lint-free cloth. 
  • The part is sufficiently clean if the cloth remains clean
  • The part still contains soil residue if the cloth becomes soiled or discolored

Gravimetric testing:

  • It involves filtering a contaminated sample through a control filter and a sample filter
  • Place two pre-weighed filters, one on top of the other, in a single filter holder
  • Sample contaminants will be retained entirely by the top test filter
  • Both filters are subjected to identical alterations in tare weight as a result of moisture
  • Any change in the weight of the bottom (“control”) filter is then applied as a correction to the weight of the contaminant
  • Results accurate to 0.1 mg are routinely attained using this method

How do I schedule a free test cleaning consultation for my parts?

Better Engineering uses all of the above these methods and more to assess and ensure the proper cleanliness in the parts washing process. BE has a full engineering lab and machine demonstration center to test and clean your parts according to your application. For a complimentary parts washing consultation, contact Better Engineering via email or phone at 1-800-229-3380.


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